Ocular migraines are common variations of migraine headaches. They are apparently
caused by the same body malfunctioning as a classical migraine: a sudden constriction of
blood vessels, known as a vascular spasm. However, these temporary spasms are thought to
occur in the blood vessels of the retina (the delicate lining in the back of one's eyes), or
in changes across the retina's nerve cells. They can affect one or both eyes, and usually
are harmless and resolve without any medication.

An ocular migraine typically begins with a visual disturbance beginning in the side
vision, usually consisting of a ring (changing to solid) semi-circular, jagged-edged, shimmering
lightness, usually pale pastel. This disturbance
often distorts or clouds the vision within the light area.

Symptoms

Symptoms can be quite varied and related to possible underlying problems.

Normal ocular migraine symptoms include:

A blank spot in the visual field

Flickering colored lights in the periphery of vision

Zig zag lines in the visual field

Blurred area of vision, mostly around the periphery, as though you are looking at heat waves rising off hot pavement.

Note: "Regular" migraines appear to occur due to
constriction and dilation of fine arteries in the head and can be
intensely painful. The pain often stays on
one side of the head, and might be accompanied by nausea and vomiting.

If an ocular migraine is followed by a one-sided headache that throbs, it is called a "migraine with aura."

Causes of Ocular Migraines

Some scientists think that ocular (visual) migraines are caused by triggered inflammatory substances released in the tissues surrounding the circulatory and nerve system of the
head and brain.

Ocular migraines may be due to stress and fatigue - the same probable causes of migraine headaches. Learn more about migraine headaches,
computer eye-fatigue. These related causes can include improper glasses and other conditions
such as hypertension, sinus conditions, tumors, hormonal changes, certain foods such as alcohol, aged cheese, MSG or chocolate, or other allergies rather than due to problems related to the eyes.

However, while scientists are not sure exactly what causes ocular migraines, they do appear to be tied to blood vessel spasms in the retina, or in the back of the eye in the vessels
that supply the retina with blood. They may be due to other changes in the optic nerve.

An ocular migraine can appear simultaneously with a migraine headache.

Conventional Treatment

Ocular migraines tend to go away after a few minutes to an hour and generally treatment is not needed. However, if you have them repeatedly
it will be a good idea to have an exam. Normal practice is for a medical doctor to get your complete medical history and give you a thorough
physical exam to rule out causes of the headache from other physical conditions. An ophthalmologist
can verify that
eye-related problems are not contributing to the condition.

Similarly, if you have frequent migraine headaches, you should talk to your health care professional.